Anaplastic thyroid tumors. Immunohistology

Area of Science:

• Oncology
• Pathology
• Endocrinology

Background:

• Anaplastic thyroid tumors (ATTs) are aggressive malignancies with complex cellular origins.
• Accurate classification of ATTs is crucial for effective treatment strategies.

Purpose of the Study:

• To investigate the expression of hormonal, epithelial, and sarcoma markers in ATTs.
• To determine the frequency of these markers and their correlation with histologic patterns.

Main Methods:

• An avidin-biotin immunoperoxidase technique was employed.
• 29 anaplastic thyroid tumors were analyzed for thyroglobulin (TG), calcitonin (CT), epithelial membrane antigen, keratin, desmin, alpha-1-antichymotrypsin (ACT), and vimentin.

Main Results:

• 27% of ATTs stained positive for thyroglobulin (TG); none stained for calcitonin (CT).
• Epithelial markers were present in 55%, alpha-1-antichymotrypsin (ACT) in 48%, and vimentin in 47%.
• Keratin and vimentin coexpression occurred in 39% of cases. Marker expression did not correlate with histologic pattern. 30% of ATTs showed no differentiation markers.

Conclusions:

• ATTs exhibit diverse differentiation profiles, with frequent expression of epithelial and sarcoma markers.
• A notable subset of ATTs lacks differentiation markers, posing diagnostic challenges.
• Immunohistochemical analysis aids in characterizing ATTs, though complete differentiation is often absent.